Gas turbine engines generally include a compressor to pressurize inflowing air, a combustor to burn a fuel in the presence of the pressurized air, and a turbine to extract energy from the resulting combustion gases. The turbine may include multiple rotatable turbine blade arrays separated by multiple stationary vane arrays. The turbine blades are coupled to a rotor disk assembly which is configured to rotate about an engine axis. The turbine blades and vanes, as well as the rotor disk assembly, are subject to relatively high temperatures. Accordingly, compressed air from the compressor section is channeled to the turbine section where it can be directed through the rotor disk assembly and cool various components of the rotor disk assembly.